1// Copyright 2014 The Chromium Authors. All rights reserved. 2// Use of this source code is governed by a BSD-style license that can be 3// found in the LICENSE file. 4 5#ifndef COMPONENTS_METRICS_SERIALIZATION_SERIALIZATION_UTILS_H_ 6#define COMPONENTS_METRICS_SERIALIZATION_SERIALIZATION_UTILS_H_ 7 8#include <string> 9 10#include "base/memory/scoped_ptr.h" 11#include "base/memory/scoped_vector.h" 12 13namespace metrics { 14 15class MetricSample; 16 17// Metrics helpers to serialize and deserialize metrics collected by 18// ChromeOS. 19namespace SerializationUtils { 20 21// Deserializes a sample passed as a string and return a sample. 22// The return value will either be a scoped_ptr to a Metric sample (if the 23// deserialization was successful) or a NULL scoped_ptr. 24scoped_ptr<MetricSample> ParseSample(const std::string& sample); 25 26// Reads all samples from a file and truncate the file when done. 27void ReadAndTruncateMetricsFromFile(const std::string& filename, 28 ScopedVector<MetricSample>* metrics); 29 30// Serializes a sample and write it to filename. 31// The format for the message is: 32// message_size, serialized_message 33// where 34// * message_size is the total length of the message (message_size + 35// serialized_message) on 4 bytes 36// * serialized_message is the serialized version of sample (using ToString) 37// 38// NB: the file will never leave the device so message_size will be written 39// with the architecture's endianness. 40bool WriteMetricToFile(const MetricSample& sample, const std::string& filename); 41 42// Maximum length of a serialized message 43static const int kMessageMaxLength = 1024; 44 45} // namespace SerializationUtils 46} // namespace metrics 47 48#endif // COMPONENTS_METRICS_SERIALIZATION_SERIALIZATION_UTILS_H_ 49